#region License Information
/* HeuristicLab
* Copyright (C) 2002-2015 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
*
* This file is part of HeuristicLab.
*
* HeuristicLab is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* HeuristicLab is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with HeuristicLab. If not, see .
*/
#endregion
using System;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Data;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
namespace HeuristicLab.Encodings.IntegerVectorEncoding {
///
/// Rounded average crossover for integer vectors.
///
[Item("RoundedAverageCrossover", "Average crossover for integer vectors.")]
[StorableClass("22319477-6A9C-46CA-B520-6F0F43476BC2")]
public class RoundedAverageCrossover : BoundedIntegerVectorCrossover, IBoundedIntegerVectorOperator {
[StorableConstructor]
protected RoundedAverageCrossover(bool deserializing) : base(deserializing) { }
protected RoundedAverageCrossover(RoundedAverageCrossover original, Cloner cloner) : base(original, cloner) { }
public RoundedAverageCrossover() : base() { }
public override IDeepCloneable Clone(Cloner cloner) {
return new RoundedAverageCrossover(this, cloner);
}
///
/// Performs an average crossover of the two given parent integer vectors.
/// The average is rounded and mapped to the nearest valid value (e.g. if step size is > 1)
///
/// A random number generator.
/// The parents for crossover.
/// The bounds matrix that contains for each dimension one row with minimum (inclusive), maximum (exclusive), and step size columns.
/// If the number of rows is smaller than the number of dimensions the matrix is cycled.
/// The newly created integer vector, resulting from the single point crossover.
public static IntegerVector Apply(IRandom random, ItemArray parents, IntMatrix bounds) {
int length = parents[0].Length, parentsCount = parents.Length;
if (parents.Length < 2) throw new ArgumentException("RoundedAverageCrossover: The number of parents is less than 2.", "parents");
if (bounds == null || bounds.Rows < 1 || bounds.Columns < 2) throw new ArgumentException("AverageCrossover: Invalid bounds specified.", "bounds");
var result = new IntegerVector(length);
try {
double avg;
for (int i = 0; i < length; i++) {
avg = 0;
for (int j = 0; j < parentsCount; j++)
avg += parents[j][i];
avg /= parentsCount;
int min = bounds[i % bounds.Rows, 0], max = bounds[i % bounds.Rows, 1], step = 1;
if (bounds.Columns > 2) step = bounds[i % bounds.Rows, 2];
max = FloorFeasible(min, max, step, max - 1);
result[i] = RoundFeasible(min, max, step, avg);
}
} catch (IndexOutOfRangeException) {
throw new ArgumentException("RoundedAverageCrossover: The parents' vectors are of different length.", "parents");
}
return result;
}
///
/// Performs an average crossover between two parent integer vectors.
///
/// Thrown if there are not exactly two parents.
/// A random number generator.
/// An array containing the two integer vectors that should be crossed.
/// The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).
/// The newly created integer vector, resulting from the average crossover.
protected override IntegerVector CrossBounded(IRandom random, ItemArray parents, IntMatrix bounds) {
return Apply(random, parents, bounds);
}
}
}